1. Field of the Invention
The present invention relates to an intermediate transfer device and an image forming apparatus.
2. Description of the Related Art
In an image forming apparatus that primarily transfers toner images onto an intermediate transfer belt and that secondarily transfers the toner images onto a recording medium such as a paper sheet, it is necessary to remove toners (transfer residual toners) remaining on a toner carrying surface of the intermediate transfer belt.
Normally, as the intermediate transfer belt, a belt that has no elasticity in a stretching direction is employed. In recent years, there has been proposed an image forming apparatus using an elastic intermediate transfer belt to realize improvement in adhesiveness to a photoreceptor and the like, thereby enabling the enhancement of an image quality and the design of a smaller image forming apparatus at low cost.
For example, Japanese Patent Application Laid-Open No. 2003-98839 discloses a cleaner that employs an elastic intermediate transfer belt, that includes a cleaning roll in contact with the intermediate transfer belt at positions opposed to a stretching roll, that causes the intermediate transfer belt to be along a part of a peripheral surface of each cleaning roll, and that includes an auxiliary roll that presses the intermediate transfer belt.
According to the cleaner structured as described in the Japanese Patent Application Laid-Open No. 2003-98839, the cleaning roll is moved away from the intermediate transfer belt, and this operation sometimes causes the intermediate transfer belt to be sandwiched between the cleaning roll and the stretching roll or the cleaning roll and the auxiliary roll. The probability of sandwiching the intermediate transfer belt therebetween is higher, in particular in case of unevenness occurred during the manufacture or assembly of the cleaning roll and the like. Because the intermediate transfer belt is elastic, a degree of expansion and contraction of the belt changes when being partially put between the rolls during circulation.